Circulating space heater and venting means therefor



June 6, 1939. A. w. LUNDSTRUM CIRCULATING SPACE HEATER-AND VENTING MEANS THEREFOR 3 Sheets-Sheet 1 Filed April 6, 1936 \l r I Z ALL/4N W. LL/NDFTF? L/M INVENTOR ICTTORNEY June 6, 1939- A. w. LUNDSTRUM 2,160,383

CIRCULATI NG SPACE HEATER AND VENTING MEANS THEREFOR Filed April 6, 1936 3 Shets-Sheet 2 411% R m w l W- m W M W m m T'PW W- 5 I z m w N A M 2 m MW HIM 5 n June 6, 1939. A'. w. LUNDSTRUM 2,160,883

CIRGULATING SPACE HEATER AND VENTING MEANS THEREFOR Filed April 6, 1936 3 Sheets-Sheet 3 ALL/4N vv LL/NDETRL/M INVENTQR ATTORNEY Patented dunes, 1339 I I i v I UNITEDSTATES PATENT OFFICE CIRCULATING SPACE HEATER AND VENT- ING MEANS THEREFOR Allan W. Lundstrum, Portland, Oreg- Application April 6, 1936, Serial 'No. 72,900 Claims. (Cl. 126-85) This invention is directed to circulating space ticularly to those using liquid and gaseous fuels. heaters and more particularly to the gas fired Moreover, it is to be understood that the combustype. One of the principal objectsof the invention chamber may be disposed anywhere and may tion is the provision of air circulating means assobe applied to a wide variety of uses where a heat- .3 ciated with the heater for producing a uni-direcing chamber that is sealed with respect to the 5 tional draft through the air intake and flue paswork being dealt with, is required, for example; sages thereof, under any and all wind conditions the combustion chamber or heating chamber may existing on the exterior of the space or building be submerged in a vat, in dry rooms, in garages, within which the heater is disposed. Another and in numerous other places where an open flame l important object of the air circulating means is would be hazardous. The invention is particum toprevent a reversal of air flow therethrough larly adapted to the foregoing uses since the when a change occurs in the direction of air flow combustion chamber is entirely sealed, and its or wind conditions on the exterior of thebuild only openings are through the intake and flue ing. An intake hood associated with the air passages which extend through the wall of the intake passage is-so designed that any air current building to the exterior thereof and into open 15 impinging upon it from any direction, creates a communication with the atmosphere.

pressure in the air intake passage. An exhaust These and other objects will pp r as my hood associated with the flue passage is designed vention is more fully hereinafter described in the so that any air current impinging upon it creates following specification, illustrated in the accomgg a vacuum in the flue passage. Both'of said hoods panying drawingsand finally pointed out in the are so constructed that they may be mounted appended claims. close together in a single unit without any danger In the drawings:

of the flue gases entering the intake passage Figure 1 is a side elevation of my new and imwhich, of course, would cause re-circulation of proved heater and cabinet with parts broken away flue gases through the heater and ultimate smothfor convenience of illustration. ering of the fire or flame in the combustion cham- Figure 2 is a top plan view of Figure 1, and also her. with parts broken away.

Both of said intake and exhaust hoods form the F u e 3 is an end e evation of the heater, with terminal ends of passageways in open communiparts bro en away, n Showing e air intake 30 cation at one of their ends with the interior of and flue passages extending to the exterior of a 3n the heater. Their opposite ends extend through buildin a Wall or Window of a building to the exterior Figure 4 illustrates a semi-permanent installathereof. This particular method of extending the tier! 0 th a intake and Venting y t intake and exhaust passages through the wall of Figure 5 s a fragmentary e a V e Of a W n- 3;, the building, eliminates the necessity of chimneys (1 W frame Showing a yp a e ns o aCCOmmO- or smoke stacks which must necessarily extend dating b the r intake and Venting meansabove the highest point of a building to eliminate Fi r 6 is a r gmentary sectional view of a back drafts which interfere with proper combus- Well Showing a permanent t atio Of the air tion of fuels. intake and flue passages.

Another object of the invention is its particuur s a p p v v w of the a t k lar construction to prevent gas or the products of hood: combustion from escaping into th r Th Figure 8 is a sectional view taken on the, line combustion chamber of the heater, as well as its f Figure companion chambers, are entirely sealed with I Figure 9 is a perspective V e Venting respect to the interior of the room and their only 11006 for the flue p e openings are through the intake and flue passage Figure 10 is a sectional view taken on the line to the exterior of the room or building. iii-49 of ure The heater proper is embraced within a cab- Referring ow o e particu arly to the drawinet or housing of any approved design, which is ngst 5|) provided with suitable louvers through its side The main body of the heater consists of a cabiand end walls, and a series of heat deflecting or net or housing I of any suitable design and havspreading louvers through the upper wall thereof. ing fixed louvers 2 in its side and end walls at any Although I show and describe a gas fired heater, desired location, but preferably near the bottom.

7 it is to be understood that theinvention is ap- The top wall or cover 3 is provided with suitable s5 plicable to any combustion chamber and paropenings with which are associated a plurality of or.

deflecting vanes 4 arranged, as shown, to deflect the heat in diverging directions. The base I of her is provided with an access opening 8 and a cover-plate 9 therefor. The opposite wall of the combustion chamber is formed with an opening III to permit passage of heat into a companion chamber I I. The chamber-nil is preferably elevated from the floor of the cabinet by any suitable means such, for instance, as the leg or -sup-. port I2.

The combustion chamber is provided with any air intake tube l3 in open communication at one of its ends with the interior of the combustion chamber at its lower end. The tube l3 extends upwardly along the back of the cabinet and is adjustably connected with the terminal end of the air intake means to be more fully hereinafter described. The chamber II is provided with-a venting tube or flue passage l4 extending outwardly from the upper end of the cabinet, and adjustably connecting with an exhausting means hereinafter referred to. It is desirable to have both of these elements adjustably connected with the intake and exhaust ducts, so that window sills of various heights and walls of various thicknesses may be dealt with conveniently when installing the apparatus.

The burner I within the combustion chamber is supplied with gas through a pipe l5 which connects with a main and throttling valve 66 connected as at Ill with a mainsource of supply. The burner 7 is provided with any conventional type of fiint lighter IA, as shown, for lighting the same without the necessity of opening the cover plate 9.

Within the air space surrounding the cabinet H, I provide a humidifier in the form of a continually burning jet i8 supplied with gas from the valve is through suitable pipes i9 and which direct the supply of gas through a manually controlled valve 2|, having an actuating knob 22 disposed on the exterior of the cabinet. The supply of gas to the jet it passes through a thermostatically actuated safety valve 23 adapted to automatically turn the gas off when the flame is extinguished. In other words, the cooling of the metal strip 24 will cause the valve 23 to close, and thereby prevent escapement of unburned gases.

Humidification is accomplished by the water vapor which results from the combustion of hydrogen in the fuel supplied to the jet l8. The amount of water vapor necessary for the comfortable humidification of any space is roughly proportional to the amount of heat necessary to be supplied to that same space for human com fort. Therefore, the valve I6 is provided with two separate orifices for the purpose of supplying proportional amounts of gas to the humidifying jet l8 and the burner i.

The outer ends of the air intake and flue tubes are each connected with insulated tubes 25 adapted to pass beneath the lowermost edge of a window sash, when temporarily installed, or to be embraced by the sash, as shown in Figures 4 and 5, when installed in a semi-permanent provided for that purpose.

manner. When permanently installed. the tubes extend entirely through the wall as shown in Figure 6, and are provided with coupling flanges 28 to accommodate the flanged ends of the air intake and hue tubes.

As shown in Figure 3, the tube 26 passes beneath the window sash which is elevated sufllciently to accommodate the tube and a suitable thickness of heat insulating material 21, which alsoserves to seal the opening beneath the window.

In the semi-permanent installation, the window sash is cut out or notched, as at 28, and provided with any suitable packing or insulating material 29 to snugly embrace the tube 25. In this particular installation, the side walls of the tube and the notch are tapered, as shown, to produce a tightly sealed engagement between the two.

Although I have shown a separate tube for the air intake and the flue, it is to be understood that a single tube, suitably partitioned into two channels or passage-ways, could accomplish the same result and, in some installations I may prefer to use this type of divided tube to conserve space or to fit certain structural conditions.

'The air intake hood, shown in Figures 7 and 8, consists of a hollow body member, generally indicated at 30 and provided with a series of upper compartments 3| and a corresponding number of lower compartments 32. Both series of compartments are arranged vertically and converge toward the center section of the hood. The hood connects with and is supported by one end of a tube 33, whose opposite end connects with the tube 25 for communication with the interior of the heater, as aforesaid. An air opening 34is provided on the upper and lower walls of the tube adjacent its point of connection with the hood. The inner ends of each of the upper and lower compartments are in open communication with horizontal air ducts 35 and 36 extending into the tube 33. An intermediate duct 31 is formed by the space between the ducts 35 and 36. Each intermediate duct is separated from the one adjoining by a. wall' 39, which is formed integral with a straightening vane 39. A plurality of straightening vanes are provided which extend outwardly from the hood, as shown, and are arrangedin suitable spaced relation with respect to each other. Their object is to direct air currents, impinging upon them from any lateral direction, directly into the air duct 31, thence through the tube 33 and into the combustion chamber. The partition walls between the compartments 3| likewise straighten air currents impinging upon them and likewise direct'the air currents through the air ducts 35 and 36 and through the tube 33. Air currents impinging upon the rear face or faces of the hood are also directed through the tube 33 by passing through the air spaces 34 The tube 33 is inclined downwardly for a portion of its length to prevent water, and other foreign matter from entering the tube and, subsequently, the combustion chamber. A suitable damper may be provided at any convenient point within the tube l3 to regulate the amount of air entering the combustion chamber for proper combustion.

The exhaust hood, shown in Figures 9 and 10, connects with and is supportedby a tube 40 which is in open communication with the other of the tubes 25, as aforesaid. The tube 40 is also formed with an inclined portion to prevent foreign matter from entering the flue system. The hood consists of a venturi generally indicated at 4| and comprises a series of upper compartments 42, lower compartments 43 arrangedjvertically and in open communication with each other and with the tube 40. Each compartment is separated by straightening vanes 44 adapted to straighten and direct impinging air currents from any direction, vertically or horizontally, directly through the body member, and in so doing, create a suction or vacuum within the entire flue passage. From the foregoing, it will be seen that the air intake hood permits air passage into the combustion chamber at all times and under all conditions, and the exhaust hood, at thesame time, permits a free exhaust of the flue gases, and that both will cooperate in causing a uni-directional flow of air through the combustion chamber. Regardless of the direction from which the exterior air currents strike the hoods, or the angleat which they impinge, the circulation of air through the air intake and flue can only be in one direction, and at no time canit be reversed due to a change in direction of the impinging air currents. This feature is of extreme importance since any back drafts created in the air circulating system would instantly stifle the burner in the combustion chamber.

It will be noted that the flue gases exhaust to the atmosphere either through the extreme upper or lower ends of the flue hood 4|, and that the major quantities of air entering the air in-- Y take, as a result of a cross wind which might tend to carry the flue gases toward the air intake, do so at the center section of the hood. The important reason for this particular arrangement is so that, in the event of a cross wind flowing from the exhaust hood toward the intake hood, it will not direct the flue gases into the air in- I take. Obviously, the flue gases enter a stratum of air which is suiflciently removed from that entering the airintake, so that the two are prevented from co-mingling, and the same condition applies, regardless of the angle of approach of the air current. For instance, if the air current is approaching the top ends of both hoods, for example, in an. angular and downward direction, the air strata will be divided; one part entering the compartments 3| of the airintake, and the other part entering the upper compartments 42 of the flue hood. The flue gases will then be driven downwardly and out through the 1 bottom compartments'or the flue hood, and away from. the stratum, or path of air, entering the upper compartments of the air intake hood, and the same division of air strata will occur regardless of the direction of wind or the angle at which it impinges both hoods.

Thus, the two cooperating hoods perform three separate and'highly important functions, namely, to produce a uni-directional flow of air through the air circulating system underall wind conditions of the atmosphere; to prevent any back drafts in the circulating system, and at the same time ofl'er no interference whatever to the system producing its own draft under normal conditions.

Having thus described the invention, what I I 2; An air intake duct and an exhaust duct in open communication at one of their ends with the interior of a cabinet and at their outer ends with the atmosphere, baflle means formed on the outer ends of the ducts for directing air currents impinging thereon into the air duct and out the exhaust duct in one direction, said means comprising air deflecting baflle means formed on the air intake duct and Venturi baifie means formed on the exhaust duct.

3. In combination with a heating device having a closed combustion chamber, air-intake and gas-exhaust 'ducts communicating. with said chamber and arranged to extend exterior of a space to be heated, baiiie means at the exterior ends of each of said ducts to cause flow into the air-intake duct and out of the exhaust duct when the wind is blowing from any direction, said bailie means being constructed to prevent admission of gases to the air-intake when the wind is blowin in a' direction from the gas-exhaust duct to the air-intake duct.

4. In a heating device having a closed combustion chamber, the combination of air-intake and gas-exhaust ducts communicating with said chamber and terminating exterior ofa space to be heated in horizontal alignment with each other, baiiie means at the exterior ends of each of said ducts to cause flow into the air-intake duct and out of the exhaust duct when the wind is blowing from any direction, said baiiie means being constructed to prevent admission of gases to the air-intake when the wind is blowing in a direction from the gas-exhaust duct to the airintake duct. 7

5. In combination with a heating device having a closed combustion chamber, air-intake and gas-exhaust ducts communicating with said chamber and arranged to extend exterior of a space to be heated, bailie means at the exterior ends of each of said ducts to cause flow into the air-dntake duct and out of the exhaust duct when l the wind is blowing from any direction, said 

